/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

/* This is the Minimalist Play Games C++ SDK sample.
 *
 * This is a tiny startup example that shows how to use
 * the gpg-cpp SDK with a pure native activity, without
 * wrapping it in Java or doing any JNI calls.
 *
 * Most of this code is taken from the standard NDK
 * sample, and has no UI or other interface.
 *
 * Tap once to sign in and once to sign out.  That's
 * all it does!  See StateManager.cpp for unlocking
 * achievements and other systems.
 *
 * All gpg-cpp-specific code is marked with "gpg-cpp"
 */

// BEGIN_INCLUDE(all)
#include <jni.h>

#include <EGL/egl.h>
#include <GLES/gl.h>

#include <android/sensor.h>
#include <android/log.h>
#include <android_native_app_glue.h>

#include "StateManager.h"

#include "gpg/android_initialization.h"
#include "gpg/debug.h"

#define LOGI(...) \
  ((void)__android_log_print(ANDROID_LOG_INFO, "native-activity", __VA_ARGS__))
#define LOGW(...) \
  ((void)__android_log_print(ANDROID_LOG_WARN, "native-activity", __VA_ARGS__))

/**
 * Our saved state data.
 */
struct saved_state {
  float angle;
  int32_t x;
  int32_t y;
};

/**
 * Shared state for our app.
 */
struct engine {
  struct android_app* app;

  ASensorManager* sensorManager;
  const ASensor* accelerometerSensor;
  ASensorEventQueue* sensorEventQueue;

  int animating;
  EGLDisplay display;
  EGLSurface surface;
  EGLContext context;
  int32_t width;
  int32_t height;
  struct saved_state state;
};

/**
 * Initialize an EGL context for the current display.
 */
static int engine_init_display(struct engine* engine) {
  // initialize OpenGL ES and EGL

  /*
   * Here specify the attributes of the desired configuration.
   * Below, we select an EGLConfig with at least 8 bits per color
   * component compatible with on-screen windows
   */
  const EGLint attribs[] = {EGL_SURFACE_TYPE, EGL_WINDOW_BIT, EGL_BLUE_SIZE,
                            8,                EGL_GREEN_SIZE, 8,
                            EGL_RED_SIZE,     8,              EGL_NONE};
  EGLint w, h;
  EGLint numConfigs;
  EGLConfig config;
  EGLSurface surface;
  EGLContext context;

  EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);

  eglInitialize(display, 0, 0);

  /* Here, the application chooses the configuration it desires. In this
   * sample, we have a very simplified selection process, where we pick
   * the first EGLConfig that matches our criteria */
  eglChooseConfig(display, attribs, &config, 1, &numConfigs);

  surface = eglCreateWindowSurface(display, config, engine->app->window, NULL);
  context = eglCreateContext(display, config, NULL, NULL);

  if (eglMakeCurrent(display, surface, surface, context) == EGL_FALSE) {
    LOGW("Unable to eglMakeCurrent");
    return -1;
  }

  eglQuerySurface(display, surface, EGL_WIDTH, &w);
  eglQuerySurface(display, surface, EGL_HEIGHT, &h);

  engine->display = display;
  engine->context = context;
  engine->surface = surface;
  engine->width = w;
  engine->height = h;
  engine->state.angle = 0;

  // Initialize GL state.
  glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);
  glEnable(GL_CULL_FACE);
  glShadeModel(GL_SMOOTH);
  glDisable(GL_DEPTH_TEST);

  return 0;
}

/**
 * Just the current frame in the display.
 */
static void engine_draw_frame(struct engine* engine) {
  if (engine->display == NULL) {
    // No display.
    return;
  }

  // Just fill the screen with a color.
  glClearColor(((float)engine->state.x) / engine->width, engine->state.angle,
               ((float)engine->state.y) / engine->height, 1);
  glClear(GL_COLOR_BUFFER_BIT);

  eglSwapBuffers(engine->display, engine->surface);
}

/**
 * Tear down the EGL context currently associated with the display.
 */
static void engine_term_display(struct engine* engine) {
  if (engine->display != EGL_NO_DISPLAY) {
    eglMakeCurrent(engine->display, EGL_NO_SURFACE, EGL_NO_SURFACE,
                   EGL_NO_CONTEXT);
    if (engine->context != EGL_NO_CONTEXT) {
      eglDestroyContext(engine->display, engine->context);
    }
    if (engine->surface != EGL_NO_SURFACE) {
      eglDestroySurface(engine->display, engine->surface);
    }
    eglTerminate(engine->display);
  }
  engine->animating = 0;
  engine->display = EGL_NO_DISPLAY;
  engine->context = EGL_NO_CONTEXT;
  engine->surface = EGL_NO_SURFACE;
}

/**
 * Process the next input event.
 */
static int32_t engine_handle_input(struct android_app* app,
                                   AInputEvent* event) {
  struct engine* engine = (struct engine*)app->userData;
  if (AInputEvent_getType(event) == AINPUT_EVENT_TYPE_MOTION) {
    int32_t flags =
        AMotionEvent_getAction(event) & AMOTION_EVENT_ACTION_MASK;

    // gpg-cpp: Sign in or out on tap
    if (flags == AMOTION_EVENT_ACTION_UP ||
        flags == AMOTION_EVENT_ACTION_POINTER_UP) {

      LOGI("Motion");
      if (!StateManager::GetGameServices()->IsAuthorized()) {
        LOGI("Signing in");
        StateManager::BeginUserInitiatedSignIn();
      } else {
        LOGI("Signing out");
        StateManager::SignOut();
      }
    }

    // Make things pretty
    engine->animating = 1;
    engine->state.x = static_cast<int32_t>(AMotionEvent_getX(event, 0));
    engine->state.y =  static_cast<int32_t>(AMotionEvent_getY(event, 0));
    return 1;
  }

  return 0;
}

/**
 * Process the next main command.
 */
static void engine_handle_cmd(struct android_app* app, int32_t cmd) {
  struct engine* engine = (struct engine*)app->userData;
  switch (cmd) {
    case APP_CMD_SAVE_STATE:
      // The system has asked us to save our current state.  Do so.
      engine->app->savedState = malloc(sizeof(struct saved_state));
      *((struct saved_state*)engine->app->savedState) = engine->state;
      engine->app->savedStateSize = sizeof(struct saved_state);
      break;
    case APP_CMD_INIT_WINDOW:
      // The window is being shown, get it ready.
      if (engine->app->window != NULL) {
        engine_init_display(engine);
        engine_draw_frame(engine);
      }
      break;
    case APP_CMD_TERM_WINDOW:
      // The window is being hidden or closed, clean it up.
      engine_term_display(engine);
      break;
    case APP_CMD_GAINED_FOCUS:
      // When our app gains focus, we start monitoring the accelerometer.
      if (engine->accelerometerSensor != NULL) {
        ASensorEventQueue_enableSensor(engine->sensorEventQueue,
                                       engine->accelerometerSensor);
        // We'd like to get 60 events per second (in us).
        ASensorEventQueue_setEventRate(engine->sensorEventQueue,
                                       engine->accelerometerSensor,
                                       (1000L / 60) * 1000);
      }

      break;
    case APP_CMD_LOST_FOCUS:
      // When our app loses focus, we stop monitoring the accelerometer.
      // This is to avoid consuming battery while not being used.
      if (engine->accelerometerSensor != NULL) {
        ASensorEventQueue_disableSensor(engine->sensorEventQueue,
                                        engine->accelerometerSensor);
      }
      // Also stop animating.
      engine->animating = 0;
      engine_draw_frame(engine);
      break;
      default:
        LOGI("Ignoring %d", cmd);
  }
}

/**
 * This is the main entry point of a native application that is using
 * android_native_app_glue.  It runs in its own thread, with its own
 * event loop for receiving input events and doing other things.
 */
void android_main(struct android_app* state) {
  struct engine engine;

  memset(&engine, 0, sizeof(engine));
  state->userData = &engine;
  state->onAppCmd = engine_handle_cmd;
  state->onInputEvent = engine_handle_input;
  engine.app = state;

  // Prepare to monitor accelerometer
  engine.sensorManager = ASensorManager_getInstance();
  engine.accelerometerSensor = ASensorManager_getDefaultSensor(
      engine.sensorManager, ASENSOR_TYPE_ACCELEROMETER);
  engine.sensorEventQueue = ASensorManager_createEventQueue(
      engine.sensorManager, state->looper, LOOPER_ID_USER, NULL, NULL);

  // gpg-cpp: Set platform initialization
  gpg::AndroidInitialization::android_main(state);

  // gpg-cpp:  Here we create the callback on auth operations
  auto callback = [&](gpg::AuthOperation op, gpg::AuthStatus status) {
    LOGI("OnAuthActionFinished");
    if (IsSuccess(status)) {
      LOGI("You are logged in!");
    } else {
      LOGI("You are not logged in!");
    }
    engine.animating = 1;
  };

  // gpg-cpp:  We need to check to see if there's a previous state.
  // If there was, we'll just continue, but if not we'll set up
  // gpg-cpp for the first time.
  if (state->savedState != NULL) {
    // We are starting with a previous saved state; restore from it.
    engine.state = *(struct saved_state*)state->savedState;
  } else {
    LOGI("Setting up gpg-cpp");

    // Get the platform configuration.
    gpg::AndroidPlatformConfiguration platform_configuration;
    platform_configuration.SetActivity(state->activity->clazz);

    // Now, create the game service (see StateManager.cpp)
    // and pass in our callback
    StateManager::InitServices(platform_configuration, NULL, callback);
  }

  // loop waiting for stuff to do.
  while (1) {
    // Read all pending events.
    int ident;
    int events;
    struct android_poll_source* source;

    // If not animating, we will block forever waiting for events.
    // If animating, we loop until all events are read, then continue
    // to draw the next frame of animation.
    while ((ident = ALooper_pollAll(engine.animating ? 0 : -1, NULL, &events,
                                    (void**)&source)) >= 0) {

      // Process this event.
      if (source != NULL) {
        source->process(state, source);
      }

      // If a sensor has data, process it now.
      if (ident == LOOPER_ID_USER) {
        if (engine.accelerometerSensor != NULL) {
          ASensorEvent event;
          while (ASensorEventQueue_getEvents(engine.sensorEventQueue, &event,
                                             1) > 0) {
          }
        }
      }

      // Check if we are exiting.
      if (state->destroyRequested != 0) {
        engine_term_display(&engine);
        return;
      }
    }

    if (engine.animating) {
      // Done with events; draw next animation frame.
      engine.state.angle += .01f;
      if (engine.state.angle > 1) {
        engine.state.angle = 0;
      }

      // Drawing is throttled to the screen update rate, so there
      // is no need to do timing here.
      engine_draw_frame(&engine);
    }
  }
}
